Vat dyestuff and process of preparing same



Patented May 14, 1929.

HE s AT S PATENT OFFICE.

it KARL THIESS, OF SINDLINGEN, NEAR HOCHST-ONTHE-MAIN, AND CARL JOSEJJ Mil TL- LER, KARL SGHIRMAGI'IEB, AND KARL ZAHN, OF IiIOCT'IST-ON-IHE-MAIN, GER- MANY, ASSIGNORS, BY MESITE ASSIGNMENTS, TO GRASSELLI DYESTUFF CORPORA- TION, OF NEW YORK, N. Y., A CORPORATION OF DELAW'AR-E.

VAT DYEEETUFF AND PROCEEKE OF PREPARING SAME.

No -.Dra'vving. Application filed December 20, 1923, Serial No. 681,854, and in Germany December 27, 19252.

The present invention relates to new vat dyestults and to a process of preparing the same, more particularly it relates to the dyestuffs corresponding to the general formula:

0 H l T wherein the benzene and naphthalene nuclei may be substituted. Our dyestuffs are obtainable by condensing a 2.3naphtho2:y-thiophene compound with an isatin compound which process is advantageously carried out in the presence or" an organic diluent and at elevated temperatures, and can be accelerated by the addition of a small quantity of a mineral acid. in order to obtain dyestuffs of the above given general formula which con- 2. 487 parts by weight of the dyestuii obtained'according to Example 1 are suspended for the purpose of bromination in 15 times its quantity of dry nitrobenzene andthere are then added 320 parts by weight 0t dry bromine. This mixture is slowly heated until it boils gently and kept in this state until there is no further evolution of hydrogen bromide.

The dyestuff has most probably the following formula After cooling, the mass is filtered and washed with alcohol. The dyestufifi thus obtained forms a dark claret-red powder, which,

glacial acetic acid.

ra Y i e f s GO\NII i i tain halogen as substitucnts, one may start with components containing halogen or one may introduce the halogen afterwards into the condensation product. The dyestuil's obtainable according to this invention dye wool and cotton fast tints.

The following examples illustrate the invention:

1. 200 parts by weight of QS-naphthoxy thiophen are dissolved in five times its quantity of glacial acetic acid and mixed with a solution of 805 parts of 5.7 -dibron1oisatin in After having added a little concentrated hydrochloric acid, the whole is heated until the condensation is completed The isolated dyestuil is tiltercdott, washed and preferably redissolved from co11 centrated sulphuric acid. It dyes cotton in a yellow vat violet-red tints fast to chlorine, lrier-boiling and light. The formation of: the dyestutl' takesplace probably as follows:

I 4. v422 parts by Weight of a dyestuft, ob-

v tained by condensing 2.3-naphthoxythiophen with 5-bronio-7-methylisatin, are suspended in nitrobenzene and then treated according 'to Example 2 with 320 parts by weight of brol l H O H:

5. 40 parts by Weight of the condensation product obtained from 2.3-naphthoxythiophen and 5.7-dichloroisatin are coupled with 400 parts by weight of dry c'hlorobenzene and heated with another 200 parts by weight of chlorobenzene to 120130. Now 20 parts by weight ofsulphuryl chloride are allowed to drop'slowly into the mixture and the whole is heated until the evolution of hydrochloric acid is terminated. The isolated reactionproduct forms a dark 1 claret-red powder which gives oncotton claret-red tints of a much bluer hue than that of the correspond ing tribromo product. According to its contents in chlorine (24,870) the dyestufi thus obtained must be regarded as a trichloro derivative of the 2.3-naphthoxythionaphthen-3- indolindigo. It corresponds most probably to the following formula:

WW i a 6. 38 parts by weight of the condensation products obtained from 2.3-naphthoxyt-hiophen and 6-chloro-7-methylisatin are suspended in 300 parts by weight of nitrobenzene and on addition of l6parts by weight of bromine heated until it boils gently. As soon as the evolution of hydrogen bromine is completed, the mixture is filtered off and washed with alcohol. The dyestuif thus obtained contains one atom of chlorine in the indirubin nucleus as well as 1 atom of bromine in the naphthoxythiophen' nucleus. It forms a red powder with a blue hue and dyes cotton very fast claret-red tints. The dyestufl has most probably the following formula:

II 6:0 l r O: N

Ill CHI Having now described our invention what we claim is:

1. As new products the vat dyestuffs corresponding to the general formula:

wherein the benzene and naphthalene nuclei may be substituted.

2. As new products the vat dyestuffs corresponding to the general formula:

wherein X stands for hydrogen or halogen and 3/ stands for hydrogen or any substituent.

3. As new products the vat dyestufi's corresponding to the general formula:

I wherein X and 3 stand for hydrogen or haloven. a 4. As a new product the vat dyestufi of the most probable formula:

s N a ll i l forming in a dry state a dark claret-red powder dyeing cotton claret-red tints having a blue hue.

In testimony whereof, we afiix our signatures.

KARL THIESS. CARL J OSEF MULLER. KARL SCHIRMACHER. KARL ZAHN. 

